iEEGLAB

EEGLAB plugin for intracranial EEG — stereo-EEG and ECoG — with a focus on cortico-cortical evoked potentials (CCEP) from single-pulse electrical stimulation. Continuous recordings and ordinary stimulus- or response-locked designs are supported too.

Electrodes on the subject's brain surfaces

What it does

Step	Function	Menu
Load electrode coordinates, events and clinician channel labels from BIDS sidecars	ieeglab_load	Load electrode coordinates and events
Mark / remove bad channels (BIDS channels.tsv status, seizure-zone labels)	ieeglab_bad_channels	via Load and Preprocess
Blank the stimulation artifact before filtering (CCEP)	ieeglab_blank_stim	Preprocess
Filter, epoch, baseline-correct	ieeglab_preprocess	Preprocess
CARLA adjusted common average reference (CCEP; validated against the published code)	ieeglab_carla, ieeglab_car	Preprocess
N1 detection — amplitude, latency, significance	ieeglab_detect_n1	CCEP analysis
CRP — canonical response shape and duration	run_CRP	CCEP analysis
Connectivity matrix — stimulation sites × contacts	ieeglab_ccep_matrix	CCEP analysis / Plot connectivity matrix
Electrode values on the brain (the iEEG counterpart of topoplot)	ieeglab_topoplot	Plot electrode values on brain
Export results — TSV, JSON provenance, MAT	ieeglab_export	Export results

Every step runs from the menus or from a script with an options struct, so whole datasets can be processed without clicking — see step 9 of ieeglab_tutorial.m:

EEG = pop_loadset('sub-02_ses-ieeg01_task-ccep_run-01_ieeg.set');
EEG = ieeglab_load(EEG, struct());                        % finds the BIDS sidecars
EEG = ieeglab_preprocess(EEG, struct('remove_bad_channels',true, 'apply_highpass',true, ...
        'highpass',0.5, 'apply_epoch',true, 'epoch_window',[-500 1000], ...
        'apply_car',true, 'car_method','carla', 'apply_baseline',true));
EEG = ieeglab_stats_subject(EEG, struct('export_dir','results'));   % N1, CRP, matrix, export

Requirements

• MATLAB (Statistics and Signal Processing toolboxes recommended) and EEGLAB with the firfilt plugin
• vistasoft for 3D brain surfaces
• 3D electrode coordinates in a BIDS *_electrodes.tsv
• For event-related work, events in the dataset or a BIDS *_events.tsv

Run ieeglab_check_install (or iEEGLAB > Check installation) to see what is present and what each missing piece would enable.

Tests

results = runtests('tests');   % headless; no figures, no dialogs

tests/test_carla_vs_reference.m checks CARLA against the published implementation (vendored unmodified in tests/reference/).

Documentation

Tutorial: ieeglab_tutorial.m and the wiki. Changes: CHANGELOG.md. Open work: TODO.md.

Citing

Please cite iEEGLAB (CITATION.cff) and the methods you use — each method prints its reference when it runs. Much of the CCEP methodology comes from Dora Hermes and the Multimodal Neuroimaging Lab (github.com/MultimodalNeuroimagingLab):

• Huang H., et al. (2024). CARLA: Adjusted common average referencing for cortico-cortical evoked potential data. J Neurosci Methods, 407, 110153.
• Miller K. J., et al. (2023). Canonical Response Parameterization: Quantifying the structure of responses to single-pulse intracranial electrical brain stimulation. PLoS Comput Biol, 19(5), e1011105.
• Ojeda Valencia G., et al. (2023). Signatures of electrical stimulation driven network interactions in the human limbic system. J Neurosci, 43(39), 6697–6711.
• van Blooijs D., et al. (2018). Evoked directional network characteristics of epileptogenic tissue derived from single pulse electrical stimulation. Hum Brain Mapp, 39(11), 4611–4622.

License

GPL-3.0-or-later. See LICENSE.